Several manufacturing processes, for example, photochemical processes and photoprocessing, paper manufacturing, petroleum refining, flue gas desulfurization, the production of inorganic chemicals, and canning processes, generate waste waters containing undesirable high concentrations of sulfur oxyanions. By sulfur oxyanions is meant water-soluble, inorganic sulfur-oxygen anions such as thiosulfate (S.sub.2 O.sub.3.sup.2-), tetrathionate (S.sub.4 O.sub.6.sup.2-) and trithionate (S.sub.3 O.sub.6.sup.2-) and the like. Sulfur oxyanions exhibit a chemical oxidation demand (COD) and a biological oxygen demand (BOD), parameters that are subject to environmental regulation discharge limits. Environmental regulations also limit the discharge of silver, which is contained in the waste water generated from some of the above said manufacturing processes and, most notably, from photoprocessing or industrial processes involving the use or manufacture of photochemicals. Consequently, further treatment of waste water to lower the silver content and to destroy the inorganic sulfur oxyanions is necessary.